CAIRO — Fans charged in Egypt’s deadliest soccer riot declared their innocence in the first session of their trial Tuesday, directing their anger toward police, charged with collaborating in the killing of 75 supporters of a rival team.

Nine senior officers, including six police generals and a colonel, are among the 73 people charged in the case. The officers were present in the courtroom, dressed in traditional white defendant uniforms, but they were not held in the courtroom cage with the rest of those on trial.

If the police are convicted, it would further fuel widespread speculation that the country’s much-despised Interior Ministry force allowed the bloody Feb. 1 attack on fans of a soccer club with which they have a long antagonistic history.

Most of the defendants are fans of Al-Masry, the main sports club in the Mediterranean city of Port Said, where the attack took place. The majority of the victims were fans of a rival team, Cairo’s Al-Ahly, whose supporters are credited with playing a major role in the 18-day popular uprising that toppled longtime President Hosni Mubarak last year.

Survivors of the attack charge that police allowed the attack by Al-Masry fans to deteriorate into bloodshed. Others have suggested that former regime loyalists hired thugs to infiltrate the stadium and kill Al-Ahly fans.

“Where is Mubarak?” the defendants chanted, reflecting their suspicions against the ousted regime and the justice system in Egypt.

The hearing took place in the same courtroom where Mubarak has faced charges related to the deaths of hundreds of protesters in the uprising.

“We will get them their justice or die like them,” the defendants in the courtroom cage shouted, fists pumping in the air as they referred to those killed in the riots.

One defendant told the presiding judges he had been called in by police as a witness but was arrested instead.

“They fooled me and brought me in as a witness ... and told me if I point people out they will release me,” he said.

Outside the courtroom, hundreds of Al-Ahly fans held photos of those killed and raised posters that said, “I will never forget justice for our brothers.” Some wore black T-shirts with the words, “We were killed in Port Said.”

The 30-minute killing frenzy in Port Said broke out when Al-Masry fans stormed the field just seconds after the final whistle blew, even though the home team won the match.

What happened next is not entirely clear, but according to witnesses and survivors, Al-Ahly fans were attacked with batons, knives, fireworks and other weapons. Some were tossed from the tops of bleachers. Others said they were stripped and Port Said fans carved slogans into their skin.

The lights at the stadium were abruptly turned off and the exit doors closed during the melee, forcing a stampede down a narrow corridor. The stadium gate, which was locked from the outside, was forced open by the crowd. Dozens were crushed to death there, including fans of Al-Masry. The youngest victim was 14 years old.

Prosecutor Mahmoud al-Hennawy said the attack that night was “planned” both by Al-Masry fans and thugs.

“The cutting off of the light in the stadium was intentional, and the proof is that Al-Ahly fans were thrown off bleachers and the main cause of deaths were the presence of thugs,” al-Hennawy said.

Some of the defendants face murder charges. The officers have been charged with assisting the attackers. They could face up to 10 years in prison.

Most of the victims were from Al-Ahly’s “Ultras”, an organization of the club’s most hardcore fans.

Some believe the security forces stood by to punish the Al-Ahly Ultras for their high-profile involvement in the uprising against Mubarak and in subsequent protests against Egypt’s military rulers.

Others attribute the violence in Port Said to negligence. Security forces at the stadium did little during the attack. Beforehand, they failed in routine security measures like searching fans for weapons, though both sides threatened violence.In addition to fans and police, the manager of the stadium and the technician in charge of the lights have been charged. The trial is scheduled to resume May 5.

After the riot, Egypt imposed a two-year ban on Al-Masry, while this year’s club season has been suspended.